Method and apparatus for extruding tubular members from solid billets or the like



A. M. MURPHY ETAL, METHOD AND APPARATUS FOR EXTRUDING TUBULAR Jan. 10, 1967 MEMBERS FROM SOLID BILLETS OR THE LIKE 2 Sheets-Sheet 1 Filed OCL. 21, 1963 p w VI SH E mmKN I o NM w T E T MF 7 A Y -S mw A m R 1 H FR T LA ACT Q Q \w a. \N w\ \w 1967 A. M. MURPHY ETAL 3,296,848

METHOD AND APPARATUS FOR EXTRUDING TUBULAR MEMBERS FROM SOLID BILLETS OR THE LIKE Filed Oct. 21, 1965 2 Sheets-Sheet 2 Kg 23 L7 INVENTORS ALFRED M. MHRPHY FIG.6 BY am-21am fdw w )fYMW THEIR ATTORNEYS United States Patent Ofiice 3,295,848 Patented Jan. 10, 1 E6? 3,296,848 METHOD AND APPARATUS FQR EXTRUDING TUBULAR MEMBERS FROM SOLID BILLETE OR THE LIKE Alfred M. Murphy and Carl M. Filak, Chester, and Thomas P. Long, Henrico County, Va., assignors to Reynolds Metals Company, Richmond, Va., a corporation of Delaware Filed Get. 21, 1963, Ser. No. 317,463 10 Claims. (Cl. 72265) This invention relates to an improved apparatus and method for extruding a hollow tubular length from a solid metallic billet or the like.

Heretofore, it has been relatively difficult to extrude a hollow tubular member from an aluminum-containing metallic billet because of the inherent characteristics of the aluminum-containing metallic material.

Therefore, in the past, hollow tubular members were extruded from aluminum-containing metallic material by first forming a solid cylindrical billet of the aluminumcontaining metallic material and, thereafter, drilling a hole longitudinally through the center of the billet so that a mandrel could be inserted therein and cooperate with an outer die means to extrude the hollow billet into a tubular member.

However, according to the teachings of this invention, an improved apparatus and method are provided wherein the tubular member can be extruded from a solid metallic billet or the like without requiring a hollowing of the billet before the same is placed in the extruding apparatus of this invention whereby a more economical and accurate method and apparatus are provided by this invention.

Accordingly, it is an object of this invention to provide an improved apparatus for extruding a hollow tubular member or the like from a solid metallic billet or the like, the apparatus of this invention having one or more of the novel features as set forth above or hereinafter shown or described.

Another object of this invention is to provide an improved method for extruding a hollow tubular member from a solid metallic billet or the like, the method of this invention having one or more of the novel features set forth above or hereinafter shown or described.

Other objects, uses and advantages of this invention are apparent from a reading of this description which prooeeds with reference to the accompanying drawings forming a part thereof and wherein:

FIGURE 1 is a crosssectional, fragmentary view illustrating the apparatus and method of this invention.

FIGURE 2is a fragmentary view similar to FIGURE 1 and illustrates the apparatus in another operating position thereof.

FIGURE 3 is an enlarged, fragmentary, cross-sectional view illustrating the cooperation between the mandrel of this invention and the hollow stern of this invention.

FIGURE 4 is a view similar to FIGURE 3 and illustrates the operation of the dummy block of this invention.

FIGURE 5 is a view similar to FIGURE 2 and illustrates the apparatus of this invention in another operat ing position thereof.

FIGURE 6 is an enlarged, fragmentary, cross-sectional view illustrating the cooperation of the mandrel tip means with the outer extruding die means of the apparatus of this invention.

FIGURE 7 is an enlarged, cross-sectional view taken on line 77 of FIGURE 5 with background structure removed.

FIGURE 8 is a view similar to FIGURE 7 and illustrates another embodiment of this invention.

While the various features of this invention are hereinafter described and illustrated as being particularly adaptable for extruding a hollow tubular member from an aluminum-containing metallic billet or the like, it is to be understood that the various features of this invention can be utilized singly or in any combination thereof to extrude other structures from other types of metallic material or the like.

Therefore, this invention is not to be limited to only the embodiments illustrated in the drawings, because the drawings are merely utilized to illustrate one of the wide variety of uses of this invention.

Referring now to FIGURE 1, the improved method and apparatus of this invention is generally indicated by the reference numeral 10 and comprises means for extruding a hollow tubular member 11, FIGURE 5, from. a substantially solid and cylindrical metal billet 12, FIG- URE 1, in a manner hereinafter described.

As illustrated in FIGURE 1, the apparatus 14} comprises a hollow stationary housing 13 carrying a sleeve 14 which defines a cylindrical cavity 15 therein for receiving the heated billet 12.

A plurality of collar means 16, 17, 18, 19, 2t) and 21 are respectively carried by stationary frame structures 22 and 23 in such a manner that the collars 16-21 define a passage means 5Z4 leading to the left hand end of the cavity 15 of the sleeve 14.

The collar 21 cooperates with a die retaining member 25 to hold an annular die member 26 adjacent the left hand end of the cavity 15 in a manner illustrated in FIGURE 1, the extruding die member 26 having a die insert 27 to form the outer extruding die means of the apparatus 1 in a manner hereinafter described.

As illustrated in FIGURE 1, the die means 27 is adapted to be dispoesd against the left hand end 28 of the solid billet 12 for a purpose hereinafter described.

A piercing and extruding mandrel 29 is carried by the apparatus 10 and is adapted to be moved relative to the housing 13 in a manner hereinafter described, the piercing and extruding mandrel 29 comprising a tip member 3119 and adapters 31, 32, 33, 34 and 35 secured together in aligned relation by threaded connections therebetween.

The adapter 35 of the piercing and extruding mandrel 29 is carried by a retaining means 36 which is adapted to be moved to the left or to the right by suitable rarn means for a purpose hereinafter described, the ram means being pneumatically, hydraulically or mechanically operated, as desired.

A hollow stem 37 surrounds the forward portion of the mandrel 29 and is adapted to have the end 38 thereof telescopically received in the cavity 15 of the housing 13 for a purpose hereinafter described. The other end 39 of the hollow stem 37 is secured to a movable housing structure 40 in any suitable manner, such as by a retaining collar 41 and a Wedge member 42 cooperating with a tapering surface 43 of the stem 37 to wedge the end 39 against a retainer 44 carried by the housing 4d.

Suitable ram means are operatively interconnected to the housing 40 to cause the same to move to the right or the left in FIGURE 1 for a purpose hereinafter de scribed, the ram means being hydraulically, pneumatically or mechanically operated as desired.

As illustrated in FIGURES 1 and 3, the adapter 31 and tip 30 of the piercing and extruding mandrel 29 have outside diameters thereof substantially smaller than the inside diameter of the stem 3'7 to facilitate relative movement therebetween.

However, the adapter 31 of the piercing and extruding mandrel 29 has a plurality of circumferential lands 415, FIGURES 1 and 3, adapted to slidingly engage the internal peripheral surface 46 of the stem 37 to maintain alignment of the tip 30 relative to the outer die means 27 for a purpose hereinafter described.

As illustrated in FIGURES 1 and 4, an annular dummy block 47 is disposed in the cavity 15 of the housing 13 between the end 48 of the billet 12 and the end 38 of the stem 37, the dummy block 47 having a plurality of outer circumferential lands 49 adapted to slidingly and sealingly engage the internal peripheral surface 50 of the sleeve member 14 of the housing 13 in the manner illustrated in FIGURE 4 to prevent the billet 12 from extruding to the right in FIGURE 1 during the extruding operation on the billet 12 in the manner hereinafter described. Similarly, the dummy block 47 has a plurality of inwardly directed annular lands 51 adapted to sealingly and slidingly engage the external peripheral surface 52 of the adapter 31 of the piercing and extruding mandrel 29 in the manner illustrated in FIGURE 4 to prevent rightward extrusion of the billet 12 during the extruding operation hereinafter described.

As illustrated in FIGURES l and 6, the tip 30 of the extruding and piercing mandrel 29 has a substantially conical piercing end portion 53 interconnected to a substantially cylindrical extruding defining surface means 54 which is adapted to cooperate with the die means 27 for extruding the tubular member 11 from the billet 12 in a manner hereinafter described.

The extruding cylindrical surface 54 of the tip 30 is interconnected to a frusto-conical portion 55 of the tip 30 which, in turn, is interconnected to a substantially cylindrical portion 56 thereof which forms the right hand end of the tip 30 as illustrated in FIGURE 6.

A tapering portion 57 projects from the end 56 of the tip 30 and is externally threaded to permit the same to be detachably interconnected to the adapter 31 of the piercing and extruding mandrel 29.

Thus, it can be seen that the tip 30 of the apparatus can be changed in a relatively simple manner without requiring complete dismantling of the entire piercing and extruding mandrel 29 should the tip portion 30 thereof become damaged or need replacement because of the subsequent wear thereon.

From the above, it can be seen that the apparatus 10 of this invention has a relatively few operating parts while still permitting the same to extrude tubular members, such as pipes or the like, from a solid metallic billet 12, the tubular members 11 being in the order of forty feet in length or the like.

The operation of the method and apparatus 10 of this invention will now be described.

As illustrated in FIGURE 1, the stem 37 and piercing and extruding mandrel 29 are moved away to the right from the housing 13 of the apparatus 10 so that a heated billet 12 can be placed in the cavity of the housing 13 with the end 28 disposed against the external die means 27 of the apparatus 10.

Thereafter, the extruding and piercing mandrel 29 and hollow stem 37 are moved to the position illustrated in FIGURE 1 to close off the right hand end of the cavity 15 of the housing 13 with the dummy block disposed be tween the stem 37 and the end 48 of the billet 12.

Thereafter, with the hollow stem 37 initially held stationary in the position illustrated in FIGURE 1, the piercing and extruding mandrel 29 is moved to the left from the position illustrated in FIGURE 1 whereby the tip 30 thereof pierces the solid billet 12 in the manner illustrated in FIGURE 2 to form a bore 58 substantially therethrough. However, as the tip 30 pierces through the billet 12, the same forces a slug 59 of material through the external die means 27 in the manner illustrated in FIGURE 2 until the tip 30 has the extending surface 54 thereof disposed in the desired position relative to the external die means 27 in the manner illustrated in FIG- URE 6.

When the tip 30 pierces through the billet 12 to the position illustrated in FIGURE 6, further movement of .4 the piercing and extruding mandrel 29 is terminated and the tip 30 is held in the position illustrated in FIGURE 6 during the resulting extruding operation whereby it can be seen that the slug 59 extruded from the billet 12 is integrally interconnected to the billet 12 by an annular portion of material 60 in the manner illustrated in FIG- URE 2.

After the tip 30 has reached the position illustrated in FIGURE 2, the hollow stem 37 is moved to the left from the position illustrated in FIGURE 2 to the position illustrated in FIGURE 5 whereby it can be seen that the stem 37 pushes the dummy block 47 to the left to cause the billet 12 to extrude through the annular cavity defined between the external die means 27 and the die surface 54 of the tip 30 to provide the tubular member 11.

However, as the tubular member 11 is being extruded from the billet 12 in the manner illustrated in FIGURE 5, it can be seen that the tubular member 11 has the leading end thereof closed by the slug 59 whereby a vacuum condition is created in the tubular member 11 as the same is being extruded to the left in the manner previously described.

If this vacuum condition in the tubular member 11 were permitted to continue to exist, the same will subsequently cause a complete inward collapse of at least part of the extruded portion of the tubular member 11 because of the external air pressure surrounding the same whereby a substantial quantity of tubular stock 11 would have to be scrapped.

However, according to the teachings of the invention set forth and claimed in the copending patent application,

-now Patent No. 3,296,847, a projectile shooting means 61 is carried by the collar means 18 of the apparatus 10 and is adapted to shoot a projectile completely through the tubular member 11 at a point disposed intermediate the slug 59 and the tip 30 of the piercing and extruding mandrel 29 in the manner illustrated in FIGURE 5 to define vent passages 62 in the tubular member 11 to relieve the vacuum condition existing therein whereby the vacuum condition in the extruded tubular member 11 can be completely eliminated before the tubular member 11 emerges from the apparatus 10.

In this manner, it can be seen that the initial vacuum condition existing in the tubular member 11 will not adversely affect the resulting tubular member 11 even though the same is extruded to a considerable length, such as forty feet or the like.

After the tubular member 11 has been extruded from the billet 12 in the manner previously described, the tubular member 11 is removed from the apparatus 10 and the slug end 59 thereof is severed from the tubular member 11 whereby the tubular member 11 can be shipped, stored or further machined as desired. The cut slug 59 can then be utilized as a solid billet in another apparatus 10 which extrudes a smaller diameter tubular member 11 than the apparatus 10 illustrated in the drawings whereby no waste of metallic material is provided by the method and apparatus 10 of this inven ion.

Further, should a particular portion of the cylindrical part 54 of the tip 30 of the piercing and extruding mandrel 29 become worn after many billets 12 have been pierced and extruded by the same in the above manner, it can be seen that by merely making a simple adjustment on the ram means operating the piercing and extruding mandrel 29, the tip 30 thereof can come to rest relative to the external die means 27 in a new position thereof whereby a new portion of the surface of the cylindrical part 54 thereof will cooperate with the die means 27 to extrude the tubular member 11 in the manner previously described.

In addition, should the entire surface of the cylindrical part 54 of the tip 30 subsequently become worn so that the tubular member 11 extruded thereby will not have the desired wall thickness, the tip member 30 can be removed from the mandrel 29 and machined down to provide a tip 30 for another apparatus which extrudes a smaller diameter tubular member 11 whereby it can be seen that the life of one tip 30 for the apparatus 10 of this invention can be relatively long.

While the apparatus 16' illustrated in the drawings and previously described is being utilized for extruding a cylindrical tubular member 11, because of the configuration of the tip member 30 in the manner illustrated in FIGURE 7, it is to be understood that the tip 31} could be so constructed and arranged in cooperation with a modified external die means 27 that the apparatus 10 of this invention could extrude a tubular member 11 having any desired cross-sectional configuration.

For example, reference is made to FIGURE 8 wherein the tip 30 and die means 27 have been modified so that the same will extrude a substantially rectangular tubular member 11A whereby it can be seen that this invention is not limited to any particular configuration of the extruded tubular member.

Therefore, it can be seen that not only does this invention provide an improved apparatus for extruding a hollow tubular member from a solid metallic billet or the like, but also this invention provides an improved method for extruding such a tubular member or the like.

While the form of the invention now preferred has been disclosed as required by the statutes, other forms may be use, all coming within the scope of the claims which follow.

What is claimed is:

1. Apparatus for extruding a tubular length from a solid billet comprising a female die means, means for holding said billet adjacent said die means, a piercing mandrel means including an exchangeable extruding surface means, means for forcing said mandrel means into said billet until said extruding surface means is received in and cooperates with said die means to define an annular cavity therebetween, and means for extruding said billet through said annular cavity to form said tubular length whereby said die means forms the exterior surface of said tubular length and said extruding surface means forms the interior surface of said tubular length.

2. An exchangeable extruding surface means adapted to be affixed adjacent the front end of a piercing mandrel means of a piercing and extruding apparatus, said extruding surface means comprising, a substantially conical, piercing, front end portion, a substantially cylindrical male extruding surface having substantially the same cross section as the base of said piercing, front end portion, and a substantially frusto-conical metal-flow surface whose minor base has substantially the same cross-section as said male extruding surface.

3. The apparatus according to claim 2 wherein said exchangeable extruding surface means comprises further a substantially cylindrical rear portion contiguous with and immediately to the rear of said frusto-conical metalfiow surface and whose cross-section is substantially the same as the cross-section of the major base of said frustoconical metal-flow surface.

4. The apparatus according to claim 3 wherein said exchangeable extruding surface means includes further a threaded connecting member extending rearwardly of said rear portion.

5. Apparatus for piercing and extruding a solid metal billet to form metal tubing comprising, a female die means, means defining a cavity adjacent said die means for receiving said billet, a piercing mandrel means having adjacent its front end an exchangeable extruding surface means including, from front to rear, and contiguously, a substantially conical, piercing, front end portion, a substantially cylindrical male extruding surface having substantially the same cross-section as the base of said piercing, front end portion, and a substantially frusto-conical metal-flow surface whose minor base has substantially the same crosssection as said male extruding surface, means for forcing said mandrel means front end portion into said billet to force a slug of said billet through said die means until said extruding surface means is received in and cooperates with said die means to define an annular cavity therebetween which is filled with a portion of said billet interconnecting said slug with the remainder thereof, plunger means receivable in said cavity and means for moving said plunger means toward said die means to extrude said billet through said annular cavity to form said metal tubing whereby said die means forms the exterior surface of said metal tubing and said extruding surface means forms the interior surface of said metal tubing.

6. The apparatus according to claim 5 wherein said exchangeable extruding surface means includes further a substantially cylindrical rear portion contiguous with and immediately to the rear of said frusto-conical metal-flow surface and whose cross-section is substantially the same as the cross-sections of both the major base of said frustoconical metal-flow surface and the forward end of the remaining portion of said mandrel means.

7. The apparatus according to claim 6 wherein said exchangeable extruding surface means is connected to said remaining portion of said mandrel by means of a threaded connecting member extending rearwardly of said rear portion of said tip.

8. Apparatus as set forth in claim 5 wherein said plunger means includes a hollow dummy telescoping said mandrel and engaging said billet.

9. Apparatus as set forth in claim 5 wherein said plunger means is hollow and receives said mandrel.

10. Apparatus as set forth in claim 9 wherein said mandrel has land means cooperable with said hollow plunger means to center said mandrel relative to said die means.

References Cited by the Examiner UNITED STATES PATENTS 924,005 6/1909 Schwieger 72265 2,721,651 10/1955 Roth 72--48l 2,778,493 1/1957 Kreidler 72265 2,903,130 9/1959 Reichl 27-481 3,008,187 11/1961 Slade 72481 CHARLES \V. LANHAM, Primary Examiner.

H. D. HOINKES, Assistant Examiner.

Disclaimer 3,296,848.Alfred M. Murphy, and Carl M. Filak, Chester, and Thomas P. Long, Henrico County, Va. METHOD AND APPARATUS FOR EXTRUDING TUBULAR MEMBERS FROM SOLID BILLETS OR THE LIKE. Patent dated Jan. 10 1967. Disclaimer filed July 2, 1971, by the. assignee, Reynolds Metals Oompany.

Hereby enters this disclaimer to claim 1 of said patent.

[O ficial Gazette Septembm 28, 1971.] 

1. APPARATUS FOR EXTRUDING A TUBULAR LENGTH FROM A SOLID BILLET COMPRISING A FEMALE DIE MEANS, MEANS FOR HOLDING SAID BILLET ADJACENT SAID DIE MEANS, A PIERCING MANDREL MEANS INCLUDING AN EXCHANGEABLE EXTRUDING SURFACE MEANS, MEANS FOR FORCING SAID MANDREL MEANS INTO SAID BILLET UNTIL SAID EXTRUDING SURFACE MEANS IS RECEIVED IN AND COOPERATES WITH SAID DIE MEANS TO DEFINE AN ANNULAR CAVITY THEREBETWEEN, AND MEANS FOR EXTRUDING SAID BILLET THROUGH SAID ANNULAR CAVITY TO FORM SAID TUBULAR LENGTH WHEREBY SAID DIE MEANS FORMS THE EXTERIOR SURFACE OF SAID TUBULAR LENGTH AND SAID EXTRUDING SURFACE MEANS FORMS THE INTERIOR SURFACE OF SAID TUBULAR LENGTH. 